Vertical strabismus resulting from an anomalous extraocular muscle

Unusual ocular motility abnormalities have been rarely reported to result from anomalous extraocular structures.^1-9 These structures, which may be either muscular or fibrotic, attach to the globe and produce a mechanical restriction resulting in incomitant strabismus. To our knowledge, we report the first patient with an anomalous extraocular muscle in whom the clinical, radiologic, surgical, and histopathologic findings are described.